18699

Appears in sequences

• Numbers that are the sum of 3 positive 7th powers.at n=14A003370
• Numbers that are the sum of at most 3 positive 7th powers.at n=28A004865
• a(n) = ceiling(n*phi^19), where phi is the golden ratio, A001622.at n=2A004974
• a(n) = least m such that if r and s in {F(h)/F(2*h): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k, where F = A000045 (Fibonacci numbers).at n=19A024831
• a(n) = least m such that if r and s in {|F(h+1)-tau*F(h)|: h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k, where F = A000045 (Fibonacci numbers) and tau = (1+sqrt(5))/2 (golden ratio).at n=19A024849
• a(1) = 1; a(n+1) = a(n) + (largest triangular number <= a(n)).at n=15A060985
• a(n) = 2^n + 3^n + 4^n.at n=7A074526
• a(n) = A014217(n+3) - A014217(n).at n=18A153263
• Multiples of 23 whose digit reversal + 1 is also a multiple of 23.at n=32A166393
• Numbers k that divide 10^(k+1)-1.at n=41A175203
• Numbers which are the sums of consecutive seventh powers.at n=9A217847
• Composite numbers k such that k*phi(k) is in A002378.at n=16A256545
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 345", based on the 5-celled von Neumann neighborhood.at n=29A271295
• Indices of primes in tribonacci sequence A000073.at n=9A303263
• Expansion of Sum_{0<i<j<k<l} q^(i+j+k+l)/( (1-q^i)*(1-q^j)*(1-q^k)*(1-q^l) )^2.at n=17A365664
• a(n) = Sum_{k=0..floor(n/3)} binomial(n-3*k,floor(k/3)).at n=56A376696
• Length of the shorts leg in the unique primitive Pythagorean triple whose inradius is A000032(n) and such that its long leg and its hypotenuse are consecutive natural numbers.at n=19A380821